How many neighbors do you have? How big is your neighborhood? Population density measures the number of people in a certain area. We usually talk about population density as the number of people in a square mile. There are benefits and drawbacks to both high- and low-density areas.

How Green Is My Valley?

Geographers use polygons to calculate area. Since most cities and counties are not regular polygons, geographers must divide areas into smaller pieces and then calculate the area of each section. Computers enable them to cut an area into many tiny polygons. This gives them an accurate measurement for the area of a city. If a geographer knows the size of a city and its population, she can calculate the city's population density. Densely populated areas have many people living close together. Sparsely populated areas have very few people spread across large distances.

Dense urban areas can provide many benefits to their residents. Schools, libraries, and museums are within easy reach. Stores and restaurants can carry a large variety of items. Public transportation is convenient and affordable. However, city-dwellers tend to have smaller homes that lack backyards. People in less densely populated areas do not have access to as many services, but they have room for gardens and sheds on their properties. Rural areas tend to have a very low population density. This gives farmers space to raise crops and livestock. People are constantly debating over which population densities provide the best quality of life.